Tractor hitch



Feb. 12, F'.| FRA|ZER' v TRACTOR HITCH Filed June 6. 1952 3 Sheets-Sheet 1 O o O Q0 O 0 bsx) O o of y) QR s N k 5 N o N e l O 6 0 g gmmnto/o Feb. l2, 1935.

F. L. FRAIZER TRACTOR HITCH Filed June 6, 1932 3 Sheets-Sheet 2 Feb. l2, 1935. F. l.. FRAIZER 1,990,821

TRACTOR HITCH Filed June 6. 1932 3 Sheets-Sheet 3 55 ...structure Patented Feb. 12, 1935 N 1 T En Aai) Animation-aune 6, 1932, serial-imi.l einem fesrclams. romeo-14.5)

,.Ihisinvention lrelates.toautomatic hitchesfors-vvide;Such automatic strain,..operated mechanism powertraotorsandmore `.particularly to .a ,safetywhavfihg acomparatively,Awidej. range' of .adjust- .overload.devicefor..automatically..-arresting.t11e.i-.ment.enabling it torbeaccurately-Set for bre- ..-.tractor, when. the.. draft.; resistanceiexceeds a. determiner-l draft resistanceoperation.

5 predetermineddegree. K Aiurtherlpbjecti of, theinvention is topro- Not'infrequently-.abnormalconditions are..en. A.vide.,.such ...overload operated or strain.` control ...countered intheoperation of tractors employed; mechanismJncluding a draft .connection which for drawing .aplow a scraper,..excavator; orlother. may be.. adjusted to,various. ,angular `positions to apparatus or for. ordinaryhauling'. .wherein a.....thje..line of: travel ofthe tracton. andwhich will 101 stone, stump orother. obstruction I:tends: toarrest.. bequally operative inany ofi such positions` of .1.thedrawn.implement` or device..and..therebyun adjustment. duly increases the draft .strain upontheimple- With theabove primary and Zother'incidental ...ment andthetractor. as .'wellas the `'intermediate Q .ohjects invieW, as vfiif'illmore,fullyappear in the .coupling .member....Un1ess.`the .operator is fable to v...spie'ciiicationl.the inventionconsists of the fea- 151.instantlystopthetractor; breakage of.the. appa...tures of "construction,4 the iparts .and combina;- 'gnratus orcoupling is sure to result-..Variousormsj. tions thereof, `and the mode' of operation, or of.. releasable 'bitches-have, been..,here.toforeY de-fw, their equivalents,- as hereinafter describedL and vised. aswell as other, forms of tractor. arresting -se'z'tiforth inthe claims. mechanism. 20 In the present.embodiment,..means is provided wherein ,is".,.shown`:z. the preferred. but obviously ...whether it. be Vthe..c1utchcontro1 lever, aconof.' `theinvention)Fig. 1` is a side elevation of trol pedal or...other..operativelmember from an' a. p0p11lar.,f.type1ofitractor towhichthe present operative to.inoperative..icondition by.-actuating.inventionvhas been applied," the tractor drive 25 `or `.power '.meansmtherwthan theu draft..strain;;.f..wheel^orithe near side. loeing removed to better which,l in the presentinstance, isemployedfonly]'.disclose'; the V.relative location and.` connecting ...for tripping orotherwisesettingin operationthe ,..partslof ,thepresentlapparatusi .Fig- 2 iS aper- L.y independently operable arresting 4.mechanisms...spectiveyiewofthe strainor overload controlled 'The device isthus. not dependent., upon the de-` y empa'ratusi .,formingj', the 'subject matter' hereof. 30;. grec. of, draft resistancel or overloadstrain.,andi Fig. 3 is atopplanwiew, and` Fig. 4 is a longi.A .,will operate quickly .andlwithfequahfacilityg if tudinal. sectional Viewofthefassembled mecha'- 1 the. predetermined .draft resistance. is exceeded mismrremoved fromfthe' tractor.. Fig; 5 is a butslightlyaslwhen it is greatly'exceeded.".JIhew` ,transverselisectional,viewlzon'line 5`51of4 Fig. 4.

. meansY for actuating the .tractor controlffelementi" Eig; .6 is adetail viewo'f the` operative connec- 35...from its normal operative. to,` arresting orinoper-.j i tion betweenthe'adjust'able. pull rod andthetrip .-ativev position,y and the resetting meansforrsuchi 1 leveras" Wi111be )hereafter explained." .Figl 7 is .arresting Y device is entirelyindependent'of. the a detail'sideuviewfof the' actuator means .for the draft overload mechanism whichA is .employedvl, tractor control member.

merely to operate arel'eas'edetentpertain-ing,to Like, parts areindicated by'similarj'characters 401the arresting device. K

` 'fjThe object of lthe invention is .tdsmplifythe of. referencexthroughout the several views. :Referring to. the accompanying drawings, there ."iReferringQ to1 .,-the faccompanyingvr drawings, y

. l forectuating acontrolelement' of,.the, tracton not lnecessarily the, onlyform" of :embodimentl 1 construction aswell as themeans andniode'fof.V is", shownja'typical style; of .farm tractor of operatonofautomatc strainoperated arresting which 2. is; one'of. the drive -wheelsV and 3'fzthe .mechanism for power tractors whereby. such. .axle 0r spindlegfor'ailikegwheel upon thegadjacent mechanism Will not ,only be cheapenedinpconandnnlikely wget out otrepair. wreach* of-the-operator- .n A,further.object of the invention is` tov provide *Projecting-rearwardlw Nfrorr1f-f'-the frame or .5o.automaticdraft operated. arresting means for aV 1 chassisx of Y'the tractor 'beneathetheoperatorsv of sturdyeOnStructiOn,.,andjofunitarxdesign;@eboltednto the 'tractor chassisfis aifootnboardfor enabling it to be. applied to. existing tractorswit platform 7. :Projectingnabove.-thewIrame `0f.,1;he -.mi`nimum'eiort. and..disturbance. ofthetractor;tractor:andsiadjacent toifthe' steering .wheel 4 l A furthe1f..-0bje0t Ofihe ILVeIlJiOIL iS t0 DTO-.fflever 9:.-ia'ndiztheiaclutchi-oontrol lever :10, 'which, --vide.such automaticoverload..mechanismwhichir n..the vpresentfinstance, is operatively connected VV`.wmay-beassembled as aunit to facilitate ,its:,ap-.-.f)with thevoverloadnstrain controlled.; apparatus .-i-.plicationto.- existingtractorsjfby unskilled-.laboransorthatrthezclutch leverswill befautomatically-re- 6 9 e. A `further.,foloject. off-theinvention.istotpro-atraetedtosdisengage,thefdriving ,clutchxwhenv.,

`side`of' the' machine. 'The operators seat l5 is# struction, butf'will be..more`"ecient in use, posi-y `supported a upon the .rear end ,.of" the tractor j tivein;operation,:uniform ,in..action,'autom'aticj1 frame;wlhile 4 is the *steeringwheeltwithin' easy f anat-:respectively vthe.:throttlelever 8,'nthesparlgf ,50 Vg powertractorwhich willcompriselbut fewpartswfseat ifand supported-#uponhorizontal .bars 6 ever the drawn implement encounters an obstruction which offers excessive resistance.

Located beneath the platform 7 with its parallel .arms bolted yto the kframe or chassis of] -with the amplifying lever 22 and its fulcrum the tractor, isa U shapedyoke 12 whichI is ordinarily provided for the attachment of a drawn implement or vehicle which is to ber coupled to such rearwardly extending yUshaped.

yoke 12.

As thus far described;thestructure is that of a conventional form of farm tractor'which,` per se, forms no part of the present invention; The mechanism forming the subject matter hereof is mounted upon the U shaped yoke 12.` Extending transversely across the yoke 12 is a transversesupporti'ng /bar 1,3 to which is `pivotally attached upon a vertical trunnion stud14 (Fig.`

" '4) a longitudinally slotted draw bar 15 which a primary member preferably,.though not neces- I sarily, formed of parallel spaced angle bars ineel.

rests upon the transverse portion of the U j shaped yoke 12 and may beadjusted to and fro thereover about its pivotal connection with the transverse bar 13 into various angular positions as maybe necessary to accommodate different implements or drawn vehicles and when turning corners or changing the directionk of travel of the tractor and drawn device;

This slotted telescopi bar 15 comprises terconnectedv at their opposite ends by spacers or headers, the rearmostspacer being formed into a downwardly Yprojecting arm 16 `positioned beyond, that is forwardly, of the Vtransverse mounting bar `13 and` the pivotal 'connection 14 i of the drag bar thereto.` Mounted intermediate the spaced parallel angle bars 17, comprising the primary member of the drag bar',`are vtwo parallel spaced bars 18, also interconnected with'ieach other at their opposite ends and having sliding longitudinal movement relative to the bars 17. At their forward end, or, that toward the pivotal connectionofy the drag' bar, vthese longitudinally, movable inner bars .18` are provided witha spacer member 19 having overhanging sliding engageor outer end ofk the primary memberl of the dragf v bar, these inner'reciprocatory draft 'bars 18 are fslidingly mounted inthe spacer head 20,`con-' necting the ends of the lbars 17 and the bars 18 carry therebeyond a clevis, draw head, orother coupling member as may be required. The inner parallel spaced VAdraft members 18 arethus ment with the respective ,angle barsl7 at each side of the're'ciprocatory bars 18;y At the rear capable of reciprocatoryk 'movement' 'intermediate `the outer or primary draftmembers 17 and independently thereof, but are subject to swinging movementaboutthe pivotal` connection of the` bars 17 with the transverse supporting member k13 in unison wihy the movement 'of said members 17.

` Extending intermediate the ,reciprocatory i draft bars 18 and pivotally connected thereto at ing bracket 25 fixedly secured to the primary 'i '70 draft members 17. The lower end of this amplia midlength point, but whollyindependent ofthe douter or primary draft members 17, is an ampli-v fying lever 22,-'the upper end of which isv fulcrumed'in'one end of a linkY or vtie rod l24,-the.

opposite end of which is pivoted to a supportfying lever 22 is provided with a cross arm or rod 26 connected' by multiple' helical tension springs 27' witha corresponding cross rod-or bracket arm 16, which, asbeforestated, is fixed-v ly secured to the forward or inner end of the draft bar structure.

' The telescopic draw bar comprising the spaced relativelysliding members 17 and 18 together connections 24 and 25 at one end of the lever,

yand the spring connections 27 connecting the opposite end of the lever 22 with the bracket arm 16, comprise a unitary structure which is` freely movable to and fro about the pivotal connection Iof the draw bar withthe transverse mounting bar 13 of the yoke 12. Any pulling .strain rhupon the clevis or connection at the extremity of the inner bar members 18 is exerted tion of the lever withrv the link rod'24, thus enf'l abling the tensionsprings 27to` resist a greater or less pulling strain. Y The tractor karresting means operates to actuate the movable control member of the tractor,

which in the present embodiment is the clutch v release lever 10, wholly independent of the kdraft overload device heretofore described by which the arresting means is merely released for operation. Pivotally mounted at `one side of the yoke`12 is an oscillatory operator arm 32 jwith which is connected a second rock arm 33 having attached thereto one end of a retractile helical springl 34,'the opposite extremity of which is attached to a bracket 35 fixedlyr secured to the mounting yoke 12. The spring 34 tends to rock the l'operator 'arm 32 downwardly. A pivoted detent or pawl 36 pivoted rat 36' to a supporting bracket upon the, yoke 12, has engagement with a notch in the hub or head of the rock armsv 32 and 33f`to hold the arm 32 in an elevated posi-- tion against the tension of the spring 34.k To

retract the operator arm 32 against the tension of the spring 34 tosuch position thatA the detent 3 6 will engage the notch in the hub or head to) retain the arms in such position, there is provided a lever 37 pivoted concentricallyy with the rock arms 32 and 33, one arm of which lever 37 `projects laterally beneath the operator arm 32, while the opposite arm ofthe lever 37 is connected with a push rod or pedal stem 38 projectingthrough the foot board or platform 7 within easy reach of the operators foot. By depressing the pedal o r push rod 38, the lever 37 is oscillated tollift the operator arm 32 from its depressed operative position to an elevated position where it` is detained by the engagement .of Athe pawl 36.` The arm 32 is connected by'. a

link 40 with an arml 41 projecting from the clutch'control lever 10 of the tractor. The arm 41 has engagement in a slot 42 inthe upper end# of the connecting link 40 so that in normal operation of the tractor, the clutch leverv10 may be ldrawn rearwardly to disengage the clutchv by Vmanual effort without meeting with resistance from the connecting rod 40. However,

when the operator arm 32 is released by disengagement of the detent pawl 36, and'permitted to be retracted downwardly under the contractile effort of the spring 34, the pulling effort' upon the rod 40 will automatically retract the clutch controlflleverb1 10' to disengage.' thezdriving clutchtnA of :the".vtractorj'iflhis '.operation' isi effected` Vinstantly upon the disengagement of thendetentff:v

then-pull. rodiy 46;;.such'1-:rod 43V isfdrawmlongitudinally with furthennmovementfi of etheebarsl :therebyxtransmittingtmotion to'.;the:tripflever 44 'l pawlfand is'eiectedunderltheinuence of "zwhch isf.actuated'therebyxagainstGthentension l5 '-the sprin'gf 34 Whol1y..independently of the ydraft@ ofi':.f.the;fspring. 52;:L'1'Suclrapullingfzeffortfitends to ,strainfuponathez drag-fbar.;i'Thus;wha,tever.'thergoscillate .thet trips levergiout' offits .engagement be'the operating Aforce-.applied to the retraction ff- "isameand there is'fno ypossiblefdanger ofy subject-f1 fl', 'fingrthe clutch lever -and its connected parts. to .1 l undue-lstressesf and strain.' C Moreover, Whenever ""the detentpavv'l 36- isvdisengaged;Y the spring 34 T?. 151- acts=instantly to retract the clutchcontrol leverf ""lOand' thus-the arresting' operation of the trac- `tor-vis infno way dependent upon the degree of'fffA character.' of'v the-resistance encountered` andt- Whateverthefpower.4 vor. speed' of the :tractor .may

beneaththe= overhanging shoulder. offztherdetent pavvl'f''nand into;.engagement withithetcam `tace 48` upon the extended-fV tail. portion 1 of rsuchx'deifoffptheieclutchecontrol lever will alwaysbetheutentspawlrand,therebya-rockingxtheizpawlc'out 01410 be@automatically@retractedrzunder inuenceaL-z of draft strain or overla'dtransmitted to the drag bar.

2Ov In thepresent 'constructionthis draft yover-- -loadrstrain' is-utilized to' disengage' the'detent'4v "-'536whenever excessive strain is encountered.

For the purpose" of -disengaging -Vthe detentr 36T*- v"iof vwhich has-operative engagement with the detent pawlfl 36,'whilefthe otherend is connected with a lpull'rod 46 actuated bythe longitudinalv movement offtheinner'draw bars-18 upon'the* .'irownllcvement of such bars against the-tension of-` the `springs- 27.*' The A detent `pawl f' 36 is -formedf Mwith a tail' or extension; having at itsv end adja' Meent to the'pivot ofthe pawl an' undercut notch-l or shoulder 47 beneath which the end ofthe i--flpaalvl inengagement' with the hub or head ofthe' operator rockarm 32. Y* At "its'opposite" extremitythe :tail or arm ofthe'detent pawl is provided f "-'fwith a cam `face`r` 48 engaged-by theextremity of ereby release the" Aw'lidedvvith an upstanding liporflange having therein a 'transverse `slot through-Which '-f' the ""ull rod'46t projects andwhich isA providedwith an nlarged head' 51-beyond such' lip or" flange. --"-SuchA interconnection of the'y motion' transmit-f '--=thereby',` is substantially "concentric"`vvith"the l pivotalfconnection-l4 ofthe draft bar-With they'vv 1x"framebar 13. As expansion spring 52 is finter^ `t`Jposed between the ibracket 25 mounted" upon the 111 55`-drag"bar and the` upstanding flange` or lip" of *itheA tripcle'ver 44. The pull" rod 46 extends ""throu'gh a suitabled'opening? in theAu bracketv 251kv vf-and atits forward end' extends `through'a ,keeper-V or perforated lug 54 carried'bythe` inner mem"' 'H 60--bers'v 18 of'thedrawbar. The'rodI extends freely'y i" through-such keeper or 'lug 54 so that the latter"-v is'capable' of `free sliding movement' upon the rodf vl'f'withinprescribed"limits as' the bars 18 recipro-"A cate-within the'bar 17 against vthe tension ofthe retractilesprings 27. Threaded" uponn the Nexf-f=to retract-such members la'nd with lthem the miamplifyingl lever` 22 against `the -tensonf of the Y -"retracti1e fsprings"f27 to'suchfext'ent Athat the-f ffl keeper or lugl54 carried by and moving with the" fr .z cthe :spring ;34, acting :through the/armA '32.:1and

link e 40.;`;.but v'always' f with" the..l :same actuatingJ 20 power. The Vclutch. beingv disengaged..r the Adraft strainfwill: bezrelievedV and underuordinary conditions the retraction of.:..the'-:=springs' 27f-1wi11 tend-.r toJ draw l the z tractor :itself 'rearwardly against;r -the resistance ofi` the: .encounteredss'ob 25 struction.' sufficientf tor: relieve the tension.` 1..:By depressingzthe'foot pedall: orifpush rod= SSII-and thereby-:oscillating the. lever 37,1 the operator arm 32 can 4- be reset/'preparatoryto'v the'n'ext operation.v Likewise the device :maybeeresetbyBO manually .restoringfthe clutch lever? 10, which; in itsnforward movement, vvilly exert 'an upward pullingl influence upon'the` connecting rod- 40 connected. at its lower end tothe operator'arm 32 thereby elevating such.: arm until the `det'entz335 paw136 is-ireengaged.

The=construction comprises a :unitaryiassembly mounted upon. the U-shapedwyoke 12 `which may be v`attached to any of: the`^ conventional formsof farm` tractorsfl By changing-fthelfulai 40 crum connection ofI thelinkf--rodAv 24With= the amplifyinglevery 22, theA devicey isre'adily fadjustedl to differenti: overload strains f to aecomr'nodate it to'different operating-conditions.

ff From the above description it'will befappar-:ay 45 f ent that there isthus provided a deviceofthe character. described possessing the particular featuresv of advantage beforeV enumerated as" desirable, but-which obviously is susceptible of modication in its form, proportions, detail '-'coneie 50 struction and arrangement of parts Without; departingfromlthe principle involved or` sacrificing any of 'its advantages.

While in' order to complywith thevstatut, vthe inventionvhas been described in language moreL-g,y 55 orilessfspeciic as to structural'-features'r*itl is to beunderstood that the invention is not limited tothe specific features shown, 'but thatA the means :and construction herein disclosed comprise' the'preferred form of severalvmodes" 010.s 60 putting the invention into effect, and the invention is thereforeclaimed infany of -its forms or modifications Within the-legitmate 'and-valid scope' ofthe appendedclaims Havingthus described my invention,'I` claimen 65 1`.=In' an automatic overload controlwmechanism for tractors, a yielding- Vhitch for afdrawn implement, a lmovable control `member' for-fthe tractor, spring tensioned actuating mechanism therefor, adetentl normally maintaining "thefi actuating mechanism in anl inoperative condition, and trip` means normally-locking"-the--de tent against disengagement-and operatedfbyfthe excessive'` "movement v of the *yielding YV'hitch' to unlock-rthe2-detent4by its initial movementfand'r 75 connected, Ya fulcrum for said'lever connected `by further movement disengage-the detent and .f release the actuating mechanism.

2.' In an automatic overload control mechaanism for tractors, a yielding hitch for a drawn implement, a movable control member for the tractor, .a spring tensioned rock arm operatively Iconnected with the control member. and a pair? .'ofinterlocking detent members normally lockingthe rock arm against oscillation, and operatively connected with the yielding hitch -for disengagement from each other by initial excessive movement of the hitch under overload strainv and cooperating to release the arm upon further yielding movement of the hitch` `3. lIn an overload control mechanism for tractors, a .telescopic draw bar for connecting a tractor ,and a drawn implement, spring tension .means for yieldingly resisting the extension of I the telescopic draw bar under increasingl load lever withthe ,other portion of the telescopic strains, including a lever to which the extensivble portion of the draw bar is connected, a link to which the lever is fulcrumed connecting the I "draw bar, spring tension means against which lthe lever is movable bythe extension of thei draw bar, and tractor arresting means rcontrolled' by the extension of the draw'bar.

`4.V A tractor control apparatus including ya qsupporting frame enga'geable with a tractor v bar mounted thereon, a tension spring, an am- .',plifying lever adjustably connecting the spring and `draft bar to yieldingly resist extension of.

the bar, a tractor arresting means, actuating 45 means therefor independent of the draft strain chassis, a draw bar mounted thereon for bothVV alongitudinally extensible and retractible motion and lateral swinging motion, tractor arrestfing means, ,and operating meansr controlled by the extension of .the draw bar'independently of 4its swingingmotion for effecting operation of the tractor arresting means in any position of lateral swinging motion of the draw bar.

, 5. A tractor control apparatus including a kmounting engageable with a tractor chassis, a longitudinally extensible and contractible draw on said draw bar, and control means for said tractor arresting means governed bythe degreev of 'longitudinal extension of the draw bar.

6. A tractor control apparatus including a mounting, a longitudinally extensible and contractible draw bar pivoted tothe mounting for to and fro lateral swinging motion, comprising reciprocatory and nonrecprocatory portions, a

, transverse lever yto a ymedial portion of which `the `reciprocatory portion of -the draw bar is to the nonreciprocatory portion of the draw bar at vvone side thereof, a tension spring connecting the leverwith such nonreciprocatory portion of the` draw bar at the opposite Y sideV thereof,

. againstwhich themovement of the reciproca- Ytory portion of thedrawbar is effected, and a tractor arresting means governedby the movement of the reciprocatoryL portion of the draw bar against the tension of said spring.-A

7. A tractor control apparatus including af mounting, a telescopic draw bar pivoted thereto -for to and fro lateral swinging kmotion including a reciprocatory portion and a nonreciproca- 'torylportion, a transverse lever carried by the draw bar and swingingly movable to and fro therewith, said lever being operatively connectedl with both portions f of the draw bar, a spring against which the lever is operable by the recip-` y rocatoryv movement `of one portionvrelative to means.

operation of the, arresting means.

the other portion, and a ltractorarresting means i governed by relative movement of draw `bar portions. v Y, Y@ l 8. A` tractor control apparatus includingy a mounting, a telescopic draw barpivoted thereto for to and fro lateral swinging motion including -a reciprocatory portion and a nonreciprocatory portion, a -transverse lever carried by thed1'aw bar andv swingingly movable to andv fro vtherewith, said lever being medially pivoted; tothe reciprocatory portion ofi the drawpbarfga` pivotally connecting one arm of the. leverwith 'the nonreciprocatory portiony of the draw bar, a tension spring yieldingly connecting the opposite arm of the-leveralso lwitlrthe nonreciprocatory portion ofthe drawbar, and a tractor arresting means governed by the relative movementof the drayvbar parts. n i y 9. A tractor control apparatus including, a

vagainst the yielding resistance of whichv the reciprocatoryV draw bar, spring tension means go draw -bar isv extensible under draft strain influence, a tractor arrestingfmeans, a control member therefor, ra triprod disposed lin telescopic relation with. the reciprocatory draw bar, and',

adjustableY stop meanscarried by one `of said members yand engaged by thel other after predetermined relative movement ofv the draw bar, thereby y permitting a predetermined Adegree-k of longitudinal movement of the draw bar portion independently of the control member, and upon further movement operating the vcontrol member to efect operation. of thev tractor arresting 0. In a sccpic draw bar, spring tension means against the yielding resistance of` which the draw bar is extensible under draft strain in1iuence,a spring actuated arresting means for the tractorv operableindependently of the draft strain influence,

normally holding the arresting means in an in- ,operativecondition, having a lockingy notch therein, a cam surface thereon in spacedV rela.- tion with the notch, a draw bar subject to draft Y-straininfluence, and tripping means for the detent operative by the ,draft strain influenceupon the draw' barv normally engaged; in fthe notch and movabletherefrom onto the cam surface to release the tractor arresting means for independent` operation. y 12. Ina tractor control apparatus, the combination with a tractor control member,A of a sprl-ng actuated operator, an. actuatingy spring therefor,v a rod differentially connectingfthe operator with Ythe tractor control memberand having sliding connection'with one of said mmbers 4by which the control member .is operable independently of Athe operator, and the movement of the operator will'actuate the control member in one direction, a detent normally holding said operator in adjusted position with its actuating spring under tension, and means :fory automatically disengaging thel detentby the draft strain upon lthe tractor when such strain exceeds a predetermined degree to enable. the

tractor control apparatus, a tele-'f Cil 13. A draft device for vehicles including a telescopic draft bar having a relatively fixed portion and a portion mounted for reciprocatory motion relative to the fixed portion, a lever medially pivoted in transverse relation to the reciprocatory portion of the draft bar, a tension spring yieldingly connecting one arm of the lever with the relatively fixed portion and a tie member nonyieldingly connecting the opposite arm of the level` with the relatively fixed portion, whereby the retractive force of the tension spring will be amplified by said lever.

14. In a draft device of the character described, an extensible and contractable draft bar pivotally mounted for limited to and fro transverse swinging motion, yielding retractive means tending to contract the bar, a motion transmitting member responsive to extension of the draft bar, and an actuated member with which the motion transmittingr member is connected substantially concentrically with the pivotal mounting of the draft bar, whereby the transmission of motion to the actuated member will be substantially uniform in various positions of swinging adjustment of the draw bar.

15. In a draft device for vehicles, an extensible and contractable draw bar pivotally mounted for to and fro swinging motion, an actuated member operated by the extension of the draw bar and an operative connection between the actuated member and draw bar having connection with the actuated member substantially concentric with the pivotal mounting of the draw bar.

16. In a tractor control apparatus, a spring actuated tractor arresting means, a detent normally holding the arresting means in inoperative condition, a stop shoulder on said detent, and a contact surface thereon in spaced relation with the stop shoulder, a movable control member engageable alternately in locking relation with the stop shoulder and in releasing relation with the contact surface upon the detent, and draft means operative under excessive strain to move said control member to initially unlock the detent and by further movement thereof disengage the detent to release the arresting means.

17. In an overload control mechanism fon tractors, a reciprocatory draw bar for connecting a tractor with a drawn implement, tension amplifying means for yieldingly resisting longitudinal movement of the draw bar under increasing load strains, including a transverse lever to which the draw bar is connected, a swinging link to which the lever is fulcrumed connecting the lever with a stationary portion of the mechanism, spring tension means against which the lever is movable by longitudinal movement of the draw bar, and tractor arresting means controlled by such movement of the draw bar.

18. In an overload control mechanism for tractors, a reciprocatory draw bar for connecting a tractor with a drawn implement, tension amplifying means for yieldingly resisting longitudinal movement of the draw bar under increasing load strains, including a transverse lever to which the draw bar is connected, the interconnection of the bar and lever being variable to vary the leverage of the latter, and an adjustable fulcrum mounting for the lever at one side of the draw bar connected with a stationary part of the mechanism and a tension spring at the opposite side of the draw bar connecting the lever with a stationary portion of the mechanism against the yielding resistance of which the lever is movable by longitudinal movement of the draw bar, and tractor arresting means controlled by such movement of the draw bar.

19. A tractor control apparatus including a reciprocatory draw bar for connecting a tractor with a drawn implement, a tension spring, an amplifying lever adjustably connecting the spring and draft bar to yieldingly resist longitudinal movement thereof under increasing load strain, tractor arresting means, actuating means therefor independently of the draft strain on the draw bar, and control means for the tractor arresting means governed by the degree of longitudinal extension of the draw bar.

20. A tractor control apparatus including a mounting, a reciprocatory draw bar carried thereby for both reciprocatory and to and fro lateral swinging motion, a transverse lever carried by the draw bar and swingingly movable to and fro therewith, and having a fulcrum connection with the mounting, a spring against which the lever is.` operable by longitudinal movement of the draw bar, and tractor arresting means governed by the movement of the draw bar.

21. In a tractor control apparatus, a swinging carrier, a reciprocatory draw bar for connecting a tractor with a drawn implement mounted thereon for both reciprocatory and lateral swinging movement, an amplifying lever disposed transversely of the drawbar, a fulcrum connection for the lever with the mounting at one side of the draw bar, a tension spring connecting the lever with the mounting at the opposite side of the draw bar,4 and against the yielding resistance of which the draw bar is movable vunder increasing load strain, and a tractor arresting means governed by the movement of the draw bar.

22. In an automatic overload control mechanism for tractors, a yielding hitch for a drawn implement, a movable control member for the tractor, an actuator spring operatively connected with the tractor control member, a detent normally preventing operation of the tractor control member by the actuator spring, and a control member subject to overload strain upon the yielding hitch normally locking said spring controlling detent and operative by initial overload strain to unlock the detent and by further overload strain operating to disengage said detent to release the tractor control member actuating spring.

23. In an automatic overload control mechanism for tractors, a yielding hitch for a drawn implement, a movable control member for the tractor, spring means for automatically operating said tractor control member independently of the movement of the yielding hitch, a detent for holding the control member operating means in inoperative position, and a member movable with the yielding hitch upon excessive movement thereof having operative engagement with the detent in one position of adjustment for preventing the disengagement of the detent and thereby prevent release of the tractor control member operating means, and having operative engagement therewith when in an alternate position of adjustment for effecting disengagement of the detent to permit release of the tractor control member operating means.

FRANK L. FRAIZER. 

